Designation: A 988 – 98 (Reapproved 2002) Standard Specification for Hot Isostatically-Pressed Stainless Steel Flanges, Fittings, Valves, and Parts for High Temperature Service1 This standard is issued under the fixed designation A 988; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision A number in parentheses indicates the year of last reapproval A superscript epsilon (e) indicates an editorial change since the last revision or reapproval Scope 1.1 This specification covers hot isostatically-pressed, powder metal, stainless steel piping components for use in pressure systems Included are flanges, fittings, valves, and similar parts made to specified dimensions or to dimensional standards, such as in ASME specification B16.5 1.2 Several grades of martensitic, austenitic, and austeniticferritic stainless steels are included in this specification 1.3 Supplementary requirements are provided for use when additional testing or inspection is desired These shall apply only when specified individually by the purchaser in the order 1.4 This specification is expressed in both inch-pound units and in SI units Unless the order specifies the applicable “M” specification designation (SI units), however, the material shall be furnished to inch-pound units 1.5 The values stated in either inch-pound units or SI units are to be regarded separately as the standard Within the text, the SI units are shown in parentheses The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other Combining values from the two systems may result in nonconformance with the specification 1.6 The following safety hazards caveat pertains only to test methods portions 8.1, 8.2, 9.5-9.7, and Section 10 of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use A 370 Test Methods and Definitions for Mechanical Testing of Steel Products2 A 751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products2 A 923 Test Methods for Detecting Detrimental Intermetallic Phase in Wrought Duplex Austenitic/Ferritic Stainless Steels2 E 112 Test Methods for Determining the Average Grain Size4 E 165 Test Method for Liquid Penetrant Examination5 E 340 Test Method for Macroetching Metals and Alloys4 E 606 Practice for Strain-Controlled Fatigue Testing4 G 48 Test Method for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride Solution6 2.2 MSS Standard: SP 25 Standard Marking System for Valves, Fittings, Flanges, and Unions7 2.3 ASME Specifications and Boiler and Pressure Vessel Codes: B16.5 Dimensional Standards for Steel Pipe Flanges and Flanged Fittings 2.4 ASME Specification IX Welding Qualifications: SFA-5.4 Specification for Corrosion-Resisting Chromium and Chromium-Nickel Steel Covered Welding Electrodes8 SFA-5.9 Specification for Corrosion-Resisting Chromium and Chromium-Nickel Steel Welding Rods and Bare Electrodes8 SFA-5.11 Specification for Nickel and Nickel-Alloy Covered Welding Electrodes8 Referenced Documents 2.1 ASTM Standards: A 262 Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels2 A 275/A 275M Test Method for Magnetic Particle Examination of Steel Forgings3 Terminology 3.1 Definitions of Terms Specific to This Standard: 3.1.1 can, n—the container used to encapsulate the powder during the pressure consolidation process; it is partially or fully removed from the final part This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel, and Related Alloys and is the direct responsibility of Subcommittee A01.22 on Steel Forgings and Wrought Fittings for Piping Applications and Bolting Materials for Piping and Special Purpose Applications Current edition approved Mar 10, 1998 Published September 1998 Annual Book of ASTM Standards, Vol 01.03 Annual Book of ASTM Standards, Vol 01.05 Annual Book of ASTM Standards, Vol 03.01 Annual Book of ASTM Standards, Vol 03.03 Annual Book of ASTM Standards, Vol 03.02 Available from Manufacturers Standardization Society of the Valve and Fittings Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602 Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Three Park Ave., New York, NY 10016-5990 Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States A 988 – 98 (2002) Ordering Information 3.1.2 compact, n—the consolidated powder from one can It may be used to make one or more parts 3.1.3 consolidation, n—the bonding of adjacent powder particles in a compact under pressure by heating to a temperature below the melting point of the powder 3.1.4 fill stem, n—the part of the compact used to fill the can It is not integral usually to the part produced 3.1.5 hot isostatic-pressing, n—a process for simultaneously heating and forming a compact in which the powder is contained in a sealed formable enclosure usually made from metal and the so-contained powder is subjected to equal pressure from all directions at a temperature high enough to permit plastic deformation and consolidation of the powder particles to take place 3.1.6 lot, n—a number of parts made from a single powder blend following the same manufacturing practice 3.1.7 part, n—a single item coming from a compact, either prior to or after machining 3.1.8 powder blend, n—a homogeneous mixture of powder from one or more heats of the same grade 3.1.9 rough part, n—the part prior to final machining 4.1 It is the responsibility of the purchaser to specify in the purchase order all requirements that are necessary for material ordered under this specification Such requirements may include, but are not limited to, the following: 4.1.1 Quantity (weight or number of parts), 4.1.2 Name of material or UNS number, 4.1.3 ASTM designation and year of issue, 4.1.4 Dimensions (tolerances and surface finishes should be included), 4.1.5 Microstructure examination if required (5.1.4), 4.1.6 Inspection (15.1), 4.1.7 Whether rough part or finished machined (8.2.2), 4.1.8 Supplementary requirements, if any, 4.1.9 Additional requirements (see 7.2 and 17.1), and 4.1.10 Requirement, if any, that the manufacturer shall submit drawings for approval showing the shape of the rough part before machining and the exact location of test specimen material (see 9.3) TABLE Chemical Requirements Composition, % UNS Designation Grade Phosphorus, max Sulfur, max Columbium Tantalum, plus Tantalum max Carbon Manganese 0.15 max 0.15 max 1.00 max 1.00 max 0.040 0.02 0.030 0.02 1.00 max 1.0 max 1.00–2.00 11.5–13.5 11.5–13.5 0.05 max 0.50–1.00 0.030 0.030 0.60 max 3.5–5.5 11.5–14.0 0.18–0.25 1.00 max 0.030 0.030 1.00 max 0.30–0.80 11.5–12.5 0.08 max 2.00 max 0.045 0.030 1.00 max 8.0–11.0 18.0–20.0 0.035 max 2.00 max 0.045 0.030 1.00 max 8.0–13.0 18.0–20.0 0.08 max 2.00 max 0.045 0.030 1.00 max 18.0–11.0 18.0–20.0 0.030 max 2.00 max 0.045 0.030 1.00 max 8.0–11.0 18.0–20.0 0.08 max 2.00 max 0.045 0.030 1.00 max 10.0–14.0 16.0–18.0 2.00–3.00 0.030 max 2.00 max 0.045 0.030 1.00 max 10.0–14.0 16.0–18.0 2.00–3.00 0.08 max 2.00 max 0.045 0.030 1.00 max 10.0–13.0 16.0–18.0 2.00–3.00 Silicon Nickel Chromium Molybdenum Titanium Martensitic Stainless Steels S41000 S41026 S41500 S42390 13 chromium 13 chromium 0.5 molybdenum 13 chromium, nickel 12 chromium, 1.0 molybdenum, modified with vanadium 0.40–0.60 Other Elements Cu 0.50 max 0.50–1.00 0.80–1.20 Other Elements N 0.03–0.08 V 0.25–0.35 Cb 0.08–0.15 Austenitic Stainless Steels S30400A 18 chromium, nickel S30403A 18 chromium, nickel, low carbon S30451B 18 chromium, nickel, modified with nitrogen S30453 18 chromium, nickel, modified with nitrogen S31600A 18 chromium, nickel, modified with molybdenum A S31603 18 chromium, nickel, modified with molybdenum, low carbon S31651B 18 chromium, nickel, modified with molybdenum and nitrogen A 988 – 98 (2002) TABLE Continued Composition, % UNS Designation Grade S31653B 18 chromium, nickel, modified with molybdenum and nitrogen S31700 19 chromium, 13 nickel 3.5 molybdenum S31703 19 chromium, 13 nickel, 3.5 molybdenum S21904 20 chromium, nickel, manganese S31254 20 chromium, 18 nickel, molybdenum, low carbon S31725 19 chromium, 15 nickel, molybdenum S31726 19 chromium, 15 nickel, molybdenum N08367 22 chromium, 25 nickel, 6.5 molybdenum, low carbon S32654 25 chromium, 22 nickel, molybdenum, low carbon Carbon Phosphorus, Manganese max Sulfur, max Silicon Nickel Chromium Molybdenum 0.030 max 2.00 max 0.045 0.030 1.00 max 10.0–13.0 16.0–18.0 0.08 max 2.00 max 0.045 0.030 1.00 max 11.0–15.0 18.0-20.0 3.0–4.0 0.030 max 2.00 max 0.045 0.030 1.00 max 11.0–15.0 18.0–20.0 0.04 max 8.0–10.0 0.045 0.030 1.00 max 5.5–7.5 0.020 max 1.00 max 0.030 0.010 0.80 max 0.030 max 2.00 max 0.045 0.030 0.030 max 2.00 max 0.045 0.030 max 2.00 max 0.020 max Columbium Tantalum, plus Tantalum max 2.00–3.00 Titanium 3.0–4.0 19.0–21.5 Other Elements N 0.15–0.40 17.5–18.5 19.5–20.5 6.0–6.5 Other Elements Cu 0.50-1.00 N 0.18-0.22 1.00 max 13.5–17.5 18.0–20.0 4.0–5.0 Other elements N 0.20 max 0.030 1.00 max 14.5–17.5 17.0–20.0 4.0–5.0 Other Elements N 0.10–0.20 0.040 0.030 1.00 max 23.50– 25.50 20.0–22.0 6.0–7.0 Other Elements N 0.18–0.25 Cu 0.75 max 2.0–4.0 0.030 0.005 0.50 max 21.0–23.0 24.0–25.0 7.0–8.0 Other Elements N 0.45–0.55 Cu 0.30–0.60 0.030 max 2.00 max 0.030 0.020 1.00 max 4.5–6.5 21.0–23.0 2.5–3.5 0.030 max 2.00 max 0.030 0.020 1.00 max 4.5–6.5 22.0–23.0 3.0–3.5 0.030 max 2.00 max 0.035 0.010 0.60 max 3.5–5.2 26.0–29.0 0.030 max 1.20 max 0.035 0.020 max 0.80 max 6.0-8.0 24.0–26.0 0.030 max 1.0 max 0.030 max 0.020 max 0.80 max 6.0–8.0 24.0–26.0 0.030 max 1.00 max 0.030 0.010 1.00 max 6.0–8.0 24.0–26.0 3.0–4.0 Other Elements N 0.20–0.30 Cu 0.50–1.00 W 0.50–1.00 0.025 max 0.80 max 0.025 0.002 0.80 max 6.5–8.0 24.0–26.0 3.0–4.0 Other Elements Cu 1.20–2.00 W 0.80–1.20 N 0.23–0.33 Austenitic-Ferritic Stainless Steels S31803 S32205 S32950 S32750 S39274 S32760C S39277 A B C 22 chromium, 5.5 nickel, modified with nitrogen 22 chromium, 5.5 nickel, modified with high nitrogen 26 chromium, 3.5 nickel, 1.0 molybdenum 25 chromium, nickel, molybdenum, modified with nitrogen 25 chromium, nickel, modified with nitrogen and tungsten 25 chromium, nickel, 3.5 molybdenum, modified with nitrogen and tungsten 25 chromium, nickel, 3.7 molybdenum S30400, S30403, S31600, and S31603 shall have a maximum nitrogen content of 0.10 % S30451, S31651, S30453, S31653 shall have a nitrogen content of 0.10 to 0.16 % % Cr + 3.3 % Mo + 16 % N > 40 1.00–2.50 3.0-5.0 Other Elements N 0.08–0.20 Other Elements Cu 0.75 max N 0.14-0.20 Other Elements N 0.15-0.35 Other Elements N 0.24–0.32 Cu 0.50 max 2.50–3.50 Other Elements N 0.24–0.32 Cu 0.20–0.80 W 1.50–2.50 A 988 – 98 (2002) Materials and Manufacture Heat Treatment 7.1 Except as provided in 7.2, the final heat treatment of all parts shall be in compliance with the requirements of Table After hot isostatic-pressing and prior to final heat treatment, the compacts may be annealed, at the option of the producer, either as a part of the consolidation process or as a separate operation 7.2 When agreed upon by the purchaser, liquid quenching may be applied to the martensitic stainless steels in place of the furnace cool or air cool specified in Table 2, provided that such quenching is followed by tempering in the temperature ranges as required in Table Martensitic parts that are liquid quenched and tempered shall be marked “QT.” 7.3 The final heat treatment shall be performed before or after machining at the option of the producer 7.4 See Section S15 if a particular heat treatment method is specified by the purchaser in the order 5.1 Manufacturing Practice: 5.1.1 Compacts shall be manufactured by placing a single powder blend into a can, evacuating the can, and sealing it The can material shall be selected to ensure that it has no deleterious effect on the final product The entire assembly shall be heated at a temperature and placed under sufficient pressure for a sufficient period of time to ensure that the final consolidated part meets the density requirements of 8.1.1.1 One or more parts shall be machined from a single compact 5.1.2 The powder shall be prealloyed and made by a melting method capable of producing the specified chemical composition, such as but not limited to, air or vacuum induction melting, followed by gas atomization 5.1.3 When powder from more than one heat of the same grade is used to make a blend, the heats shall be mixed thoroughly to ensure homogeneity 5.1.4 The compact shall be sectioned and the microstructure examined to check for porosity and other internal imperfections It shall meet the requirements of 8.1.2 The sample shall be taken from the fill stem or from a location in a part as agreed upon by the manufacturer and purchaser 5.1.5 Unless otherwise specified in the purchase order, the manufacturer shall remove the can material from the surfaces of the consolidated compacts by chemical or mechanical methods such as by pickling or machining This may be done before or after heat treatment at the option of the manufacturer (see Note 1) Structural Integrity Requirements 8.1 Microporosity—The parts shall be free of microporosity as demonstrated by measurement of density as provided in 8.1.1 or by microstructural examination as provided in 8.1.2 8.1.1 Density Measurement: 8.1.1.1 The density measurement shall be used for acceptance of material but not for rejection of material The measured density for each material shall exceed 99 % of the density typical of that grade when wrought and in the same heat treated condition as the sample Material that fails to meet this acceptance criterion may be tested at the option of the producer, for microporosity in accordance with the microstructural examination as provided in 8.1.2 8.1.1.2 Density shall be determined for one sample from each production lot by measuring the difference in weight of the sample when weighed in air and when weighed in water and multiplying this difference by the density of water (Archimede’s principle) The equipment used shall be capable of determining density within 60.004 lb/in.3(0.10 g/cm3) 8.1.1.3 At the option of the producer, the density shall be compared to the room temperature density typical of wrought steels of the same class of grades, 0.28 lb/in.3(7.8 g/cm3) for martensitic and austenitic-ferritic grades, and 0.29 lb/in.3(8.0 g/cm3) for austenitic grades, or to the density of a wrought reference sample of the same grade heat treated in accordance with the requirements of Table (see Note 2) NOTE 1—Often, it is advantageous to leave the can material in place until after heat treatment or further thermal processing of the consolidated compact Chemical Composition 6.1 The steel, both as a blend and as a part, shall conform to the requirements for chemical composition prescribed in Table Test Methods, Practices, and Terminology of A 751 shall apply 6.1.1 Each blend of powder shall be analyzed by the manufacturer to determine the percentage of elements prescribed in Table This analysis shall be made using a representative sample of the powder The blend shall conform to the chemical composition requirements prescribed in Table 6.1.2 When required by the purchaser, the chemical composition of a sample from one part from each lot of parts shall be determined by the manufacturer The composition of the sample shall conform to the chemical requirements prescribed in Table 6.2 Addition of lead, selenium, or other elements for the purpose of rendering the material free-machining shall not be permitted 6.3 The steel shall not contain an unspecified element other than nitrogen, for the ordered grade, to the extent that the steel conforms to the requirements of another grade for which that element is a specified element having a required minimum content NOTE 2—The actual density of stainless steel varies slightly with composition and heat treatment For this reason, small differences in the measured density from the typical density for a class of grades may be the result of differences in alloy content, heat treatment, or microporosity When density values are measured that are less than the density typical of a class of grades, it is appropriate to examine the sample for microporosity by the more specific metallographic examination procedures 8.1.2 Microstructural Examination: 8.1.2.1 The microstructure when examined at 20-503, 1002003, and 1000-20003 shall be reasonably uniform and shall be free of voids, laps, cracks, and porosity 8.1.2.2 One sample from each production lot shall be examined The sample shall be taken after hot-isostatic pressing or after final heat treatment The microstructure shall meet the requirements of 8.1.2.1 A 988 – 98 (2002) TABLE Heat Treating Requirements UNS No Heat Treat Type Austenitizing/Solutioning Temperature °F (°C)A Cooling Media Quenching, Cool Tempering Temperature, to Below °F (°C) min° F (°C) Martensitic Stainless Steels S41000 Class S41000 Class S41000 Class S41000 Class S41026 S41500 S42390 anneal normalize temper anneal normalize temper anneal normalize anneal normalize anneal normalize normalize normalize and temper and temper and temper and temper and temper and temper and temper not specified not specified not required not specified not specified not required not specified not specified not specified not specified 1750 [955] 1750 [955] 1850 [1010] 1860–1960 [1015–1070] furnace cool air cool B B 400 [205] B B 1325 [725] 1325 [725] furnace cool air cool B B 400 [205] B B 1250 [675] 1250 [675] furnace cool air cool furnace cool air cool furnace cool air cool air cool air cool B B liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid liquid 400 [205] 1100 [595] B B 400 [205] 1000[540] B B 400 [205] 200 [95] 200 [95] 1150 [620] 1040-1120 [560-600] 1350–1440 [730–780] 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] [260] B 500 500 500 500 500 500 175 [260] [260] [260] [260] [260] [260] [80] B Austenitic Stainless Steels S30400 S30403 S30451 S30453 S31600 S31603 S31651 S31653 S31700 S31703 S21904 S31254 S31725 S31726 N08367 S32654 solution solution solution solution solution solution solution solution solution solution solution solution solution solution solution solution treat treat treat treat treat treat treat treat treat treat treat treat treat treat treat treat and and and and and and and and and and and and and and and and quench quench quench quench quench quench quench quench quench quench quench quench quench quench quench quench 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 1900 [1040] 2100 [1150] 1900 [1040] 1900 [1040] 2025 [1105] 2050–2160 [1120–1180] S31803 S32205 S32950 S32750 S39274 S32760 S39277 solution solution solution solution solution solution solution treat treat treat treat treat treat treat and and and and and and and quench quench quench quench quench quench quench 1870 [1020] 1870 [1020] 1825-1875 [995-1025]C 1880 [1025] 1920–2060 [1050–1125] 2010–2085 [1100–1140] 1940 [1060] B B B B B B B B B B B B B B B Austenitic-Ferritic Stainless Steels liquid liquid liquid liquid liquid liquid liquid B B B B B B A Minimum unless temperature range is listed Not applicable C 30 min/in of thickness B 8.1.2.3 If the sample fails to meet the requirements for acceptance, each part in the lot may be retested, and those that pass may be accepted 8.2 Hydrostatic Tests—After they have been machined, pressure-containing parts shall be tested to the hydrostatic shell test pressures prescribed in ASME B16.5 for the applicable steel rating for which the part is designed and shall show no leaks Parts ordered under these specifications for working pressures other than those listed in the ASME B16.5 ratings shall be tested to such pressures as may be agreed upon between the manufacturer and purchaser 8.2.1 No hydrostatic test is required for welding neck or other flanges 8.2.2 The compact manufacturer is not required to perform pressure tests on rough parts that are to be finish machined by others The fabricator of the finished part is not required to pressure test parts that are designed to be pressure containing only after assembly by welding into a larger structure The manufacturer of the compacts, however, shall be responsible, as required in 16.1 for the satisfactory performance of the parts under the final test required in 8.2 Mechanical Properties 9.1 The material shall conform to the requirements for mechanical properties prescribed in Table at room temperature 9.2 Mechanical test specimens shall be obtained from production parts or from the fill stems Mechanical test specimens shall be taken from material that has received the same heat treatment as the parts that they represent If repair welding is required (see Section 15), the test specimens prior to testing shall accompany the repaired parts if a post weld treatment is done 9.3 For normalized and tempered, or quenched and tempered parts, the central axis of the test specimen shall correspond to the 1⁄4 T plane or deeper position, where T is the maximum heat treated thickness of the represented part In addition, for quenched and tempered parts, the midlength of the A 988 – 98 (2002) TABLE Tensile and Hardness Requirements UNS Designation Tensile Strength, min, ksi (MPa) Yield Strength, min, ksi (MPa)A Elongation in in (50 mm) or 4D, min, % Reduction of Area, min, % Brinell Hardness Number 18 18 15 12 16 15 14.0 35.0 35.0 35.0 35.0 45.0 45.0 143–187 167–229 235–302 263–321 235–285 295 max 30 30 30 30 30 30 30 30 30 30 45 35 50 50 50 50 50 50 50 50 50 50 60 50 Martensitic Stainless Steels S41000 S41000 S41000 S41000 S41026 S41500 S42390 Class Class Class Class 70 (485) 85 (585) 110 (760) 130 (895) 110-135 (760–930) 115 (790) 100–125 (690–862) 40 (275) 55 (380) 85 (585) 110 (760) 90 (620) 90 (620) 75 (517) Austenitic Stainless Steels B S30400 S30403 S30451 S30453 S31600 S31603 S31651 S31653 S31700 S31703 S21904 S31254 75 (515) 70 (485)C 80 (550) 75 (515)B 75 (515)B 70 (485)C 80 (550) 75 (515)B 75 (515)B 70 (485)C 90 (620) 94 (650) 30 25 35 30 30 25 35 30 30 25 50 44 (205) (170) (240) (205) (205) (170) (240) (205) (205) (170) (345) (300) S30600 S31725 S31726 78 (540) 75 (525) 80 (550) 35 (240) 30 (205) 35 (240) 40.0 40.0 40.0 50.0 50.0 50.0 N08367 95 (655) 45 (310) 30.0 50.0 S32654 109 (750) 62 (430) 40.0 250 max S31803 S32205 S32950 S32750 S39274 S32760 S39277 90 (620) 90 (620) 100 (690) 116 (800) 116 (800) 109–130 (750–895) 118 (820) 25 25.0 15 15 15 25.0 25.0 45 30 45 50 293 max 310 max 310 max Austenitic-Ferritic Stainless Steels 65 65 70 80 80 80 85 (450) (450) (485) (550) (550) (550) (585) A Determined by the 0.2 % offset method For sections over in (130 mm) in thickness, the minimum tensile strength shall be 70 ksi (485 MPa) C For sections over in (130 mm) in thickness, the minimum tensile strength shall be 65 ksi (450 MPa) B test specimen shall be at least T from any second heat treated surface When the section thickness does not permit this positioning, the test specimen shall be positioned as near as possible to the prescribed location, as agreed to by the purchaser and the supplier 9.4 For all annealed stainless steels, the test specimen may be taken from any convenient location 9.5 Tension Tests: 9.5.1 Martensitic Stainless Steels—One tension test shall be made for each production lot in each heat treatment charge When the heat treating cycles are the same and the furnaces (either batch or continuous type) are controlled within 625°F (614°C) and equipped with recording pyrometers so that complete records of heat treatment are available, then only one tension test from each production lot of each type of part (see Note 3) and section size is required instead of one test from each production lot in each heat-treatment charge such as a flange, elbow, tee, and so forth 9.5.2 Austenitic and Austenitic-Ferritic Stainless Steels —One tension test shall be made for each production lot The tension test specimen shall be made from material accompanying the parts in final heat treatment 9.5.3 Testing shall be performed in accordance with Test Methods and Definitions A 370 using the largest feasible of the round specimens The gage length for measuring elongation shall be four times the diameter of the test section 9.6 Hardness Tests: 9.6.1 Except when only one part is produced, a minimum of two pieces/batch or continuous run as defined in 9.6.2 shall be hardness tested in accordance with Test Methods and Definitions A 370 to ensure that the parts are within the hardness limits given for each grade in Table The purchaser may verify that the requirement has been met by testing at any location on the part provided such testing does not render the part useless NOTE 3—“Type” in this case is used to describe the shape of the part A 988 – 98 (2002) TABLE Product Analysis Tolerances for Stainless SteelsA 9.6.2 When the reduced number of tension tests permitted by 9.5.1 is applied, additional hardness tests shall be made on parts or samples as defined in 9.2 scattered throughout the load At least eight samples shall be checked from each batch load and a least one check/h shall be made from a continuous run When the furnace batch is less than eight parts, each part shall be checked If any check falls outside the prescribed limits, the entire lot of parts shall be reheat treated and the requirements of 9.5.1 shall apply 9.7 Fatigue Tests—When specified in the order, the fatigue strength of austenitic stainless steel components intended for service above 1000°F (540°C) shall be determined in accordance with Section S17 Elements 10 Corrosion Testing 10.1 Corrosion testing is not required by this specification 10.2 Austenitic stainless steels shall be capable of meeting the intergranular corrosion test requirements described in Section S10 10.3 When required by the purchaser, the stainless steels shall be tested in the final heat treated condition for pitting or crevice corrosion resistance according to the procedures described in Section S11 10.4 Austenitic-ferritic stainless steels shall be capable of meeting the test requirements described in Section S12 Limit or Maximum of Specified Range, % Carbon 0.030, incl over 0.030 to 0.20 incl 0.005 0.01 Manganese to 1.00, incl over 1.00 to 3.00, incl over 3.00 to 6.00 over 6.00 to 10.00 0.03 0.04 0.05 0.06 Phosphorus to 0.040, incl 0.005 Sulfur to 0.030, incl 0.005 Silicon to 1.00, incl over 1.00 to 5.00, incl 0.05 0.10 Chromium over 10.00 to 15.00, incl over 15.00 to 20.00, incl over 20.00 to 27.50, incl 0.15 0.20 0.25 Nickel to 1.00, incl over 1.00 to 5.00, incl over 5.00 to 10.00, incl over 10.00 to 20.00, incl over 20.00 to 22.00, incl 0.03 0.07 0.10 0.15 0.20 Molybdenum to 0.20 incl over 0.20 to 0.60, incl over 0.60 to 2.00, incl over 2.00 to 7.00, incl Titanium all ranges Columbium+tantalum all ranges Tantalum to 0.10, incl Cobalt 0.05 to 0.20, incl Nitrogen to 0.19 incl over 0.19 to 0.25 over 0.25 to 0.35 over 0.35 to 0.45 over 0.45 to 0.60 Columbium 0.05 to 0.20, incl Aluminum to 0.05 incl Vanadium to 0.10 incl over 0.10 to 0.25 incl Cerium 0.03 to 0.08 11 Product Analysis 11.1 The purchaser may make a product analysis on parts supplied to this specification Samples for analysis shall be taken from midway between the center and surface of solid parts, midway between the inner and outer surfaces of hollow parts, midway between the center and surface of full-size prolongations, or from broken mechanical test specimens The chemical composition thus determined shall conform to Table with the tolerances as stated in Table 12 Reheat Treatment Tungsten Copper 12.1 If the results of the mechanical tests not conform to the requirements specified, the manufacturer may reheat treat the parts and repeat the tests specified in Section 9, but not more than twice Tolerance Over the Maximum Limit or Under the Minimum Limit to 1.00, incl to 1.00, incl 0.01 0.03 0.05 0.10 0.05 0.05 0.02 0.01B 0.01 0.02 0.03 0.04 0.05 0.01 0.01 0.01 0.02 -0.005 +0.01 0.04 0.03 A This table does not apply to heat analysis Product analysis limits for cobalt under 0.05 % have not been established and the producer should be consulted for those limits B 13 Workmanship, Finish and Appearance 13.4 Machining or Grinding Imperfections Not Classified as Injurious—Surface imperfections not classified as injurious shall be treated as follows: 13.4.1 Seams, laps, tears, or slivers not deeper than % of the nominal wall thickness or 1⁄16 in (1.6 mm), whichever is less, need not be removed If these imperfections are removed, they shall be removed by machining or grinding 13.4.2 Mechanical marks or abrasions and pits shall be acceptable without grinding or machining provided the depth does not exceed the limitations set forth in 13.4.1 Imperfections that are deeper than 1⁄16 in (1.6 mm), but which not encroach on the minimum wall thickness of the part, shall be removed by grinding to sound metal 13.4.3 When imperfections have been removed by grinding or machining, the outside dimension at the point of grinding or 13.1 The parts shall be free of scale, machining burrs, and other injurious imperfections as defined herein The parts shall have a workmanlike finish and machined surfaces (other than surfaces having special requirements) shall have a surface finish not to exceed 250 AA (arithmetic average) roughness height 13.2 At the discretion of the purchaser, finished parts shall be subject to rejection if surface imperfections acceptable under 13.4 are not scattered but appear over a large area in excess of what is considered to be a workmanlike finish 13.3 Depth of Injurious Imperfections—Linear imperfections shall be explored for depth When the depth encroaches on the minimum wall thickness of the finished parts, such imperfections shall be considered injurious A 988 – 98 (2002) TABLE Repair Welding Requirements machining may be reduced by the amount removed Should it be impracticable to secure a direct measurement, the wall thickness at the point of grinding or at an imperfection not required to be removed, shall be determined by deducting the amount removed by grinding from the nominal finished wall thickness of the part, and the remainder shall not be less than the minimum specified or required wall thickness UNS Designation Electrodes A Recommended Preheat and Interpass Temperature Range, °F (°C) Minimum PostWeld Heat Treatment Temperature °F (°C) Martensitic Stainless Steels S41000 Class E 410-15 or 16 S41000 Class E 410-15 or 16 S41026 13 % Cr, 11⁄2 % Ni, 1⁄2 % Mo S41500 13 % Cr, % Ni S42390 14 Repair by Welding 14.1 Weld repairs shall be permitted (see Section S7) only with prior approval of the purchaser and with the following limitations and requirements: 14.1.1 The welding procedure and welders shall be qualified in accordance with Section IX of the ASME Boiler and Pressure Vessel Code 14.1.2 The weld metal shall be deposited using the electrodes specified in Table except as otherwise provided in Section S13 The electrodes shall be purchased in accordance with ASME Specifications SFA-5.4, SFA-5.9, or SFA-5.11 The submerged arc process with neutral flux, the gas metal-arc welding and gas tungsten-arc welding processes, excluding flux-cored consumables, also may be used 14.1.3 Defects shall be removed completely prior to welding by chipping or grinding to sound metal as verified by magnetic particle inspection in accordance with Test Method A 275/A 275M for the martensitic, or austenitic-ferritic stainless steels, or by liquid penetrant inspection in accordance with Test Method E 165 for all grades 14.1.4 After repair welding, the welded area shall be ground smooth to the original contour and shall be completely free of defects as verified by magnetic-particle or liquid-penetrant inspection, as applicable 14.1.5 The preheat, interpass temperature, and post-weld heat treatment requirements given in Table shall be met 14.1.6 Repair by welding shall not exceed 10 % of the surface area of the part nor 331⁄3 % of the wall thickness of the finished part or 3⁄8 in (9.5 mm), whichever is less 14.1.7 No weld repairs are permitted for S41000 Classes and 400-700 (205-370) 400-700 (205-370) 400-700 (205-370) 1250 (675) 1250 (675) 1150 (620) 300-700 (150-370) 400-750 (205-400) 1050 (565) 1350-1440 (730780) Austenitic Stainless Steels S30400 E 308-15 or 16 NRB S30403 E 308L-15 or 16 NR S30451 E 308-15 or 16 NR S30453 E 308L-15 or 16 NR S31600 E 316-15 or 16 NR S31603 E 316L-15 or 16 NR S31651 E 316-15 or 16 NR S31653 E 316L-15 or 16 NR S31700 E 317-15 or 16 NR S31703 E 317L-15 or 16 NR S21904 S31254 XM-10W E NiCrMo-3 NR NR S31725 D S31726 D N08367 E NiCrMo-3 NR 2025 (1105) + WQ S32654 25 % Cr, 61 % Ni, 14 % Mo NR 2100 (1150 ) + WQ S31803 22 % Cr, 5.5 % Ni, % Mo 22 % Cr, 5.5 % Ni, % Mo 26 % Cr, % Ni, % Mo 25 % Cr, %, Ni, % Mo 25 % Cr, % Ni, % Mo, W 25 % Cr, % Ni, 3.5 Mo 25 % Cr, % Ni, % Mo, 1.5 % Cu, % W 1900 (1040) + WQC 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ 1900 (1040) + WQ NR 2100 (1150) + WQ 2100 (1150) + WQ 2100 (1150) + WQ Austenitic-Ferritic Stainless Steels 15 Inspection 15.1 The manufacturer shall afford the purchaser’s inspector all reasonable facilities necessary to satisfy him that the material is being furnished in accordance with the purchase order Inspection by the purchaser shall not interfere unnecessarily with the manufacturer’s operations All tests and inspections shall be made at the place of manufacture unless otherwise agreed upon S322205 S32950 S32750 S39274 S32760 S39277 16 Rejection 16.1 Each part that develops injurious defects during shop working operations or in service shall be rejected and the manufacturer notified 16.2 Samples representing material rejected by the purchaser shall be preserved until disposition of the claim has been agreed upon between the manufacturer and the purchaser NR NR NR NR NR NR NR NR NR NR NR NR NR NR A Electrodes shall comply with ASME SFA-5.4, and corresponding ER grades of SFA-5.9 or SFA-5.11 B NR = not required C WQ = water quench D Match filler metal is available Fabricators also have used AWS A5.14, Class ER, NiCrMo-3 and AWS A5.11, Class E, NiCrMo-3 filter metals A 988 – 98 (2002) 18.1.2 Hot isostatically-pressed parts repaired by welding shall be marked with the letter “W” following the specification designation 18.1.3 When test reports are required, the markings shall consist of the manufacturer’s symbol or name, the grade symbol, and such other markings as necessary to identify the part with the test report (18.1.1 and 18.1.2 shall apply) 18.1.4 Hot isostatically-pressed parts meeting all requirements for more than one class or grade may be marked with more than one class or grade designation, such as S30400/ S30409, S30400/S30403, etc 18.2 Bar Coding—In addition to the requirements in 18.1, bar coding is acceptable as a supplemental identification method The purchaser may specify in the order that a specific bar coding system be used The bar coding system, if applied at the discretion of the supplier, should be consistent with one of the published industry standards for bar coding If used on small parts, the bar code may be applied to the box or a substantially applied tag 17 Certification 17.1 When specified in the purchase order or contract, the purchaser shall be furnished certification that samples representing each lot have been either tested or inspected as directed in this specification and the requirements have been met When specified in the purchase order or contract, a report of the test results shall be furnished 18 Product Marking 18.1 Identification marks consisting of the manufacturer’s symbol or name (see Note 4), the heat or blend number, designation of service rating, the specification number, the designation showing the grade of material, and the size shall be stamped legibly on each part or the parts may be marked in accordance with Standard SP 25 and in such position so as not to injure the usefulness of the part The specification number marked on the part need not include specification year of issue and revision letter NOTE 4—For purposes of identification marking, the manufacturer is considered the organization that certifies the piping component was manufactured, sampled, and tested in accordance with this specification and the results have been determined to meet the requirements of this specification 19 Keywords 19.1 austenitic stainless steels; austenitic-ferritic stainless steel; gas-atomized powder; hot isostatically-pressed stainless steel parts; martensitic stainless steel; pipe fittings, steel; piping applications; pressure containing parts; stainless steel fittings; stainless steel flanges; steel valves; temperature service applications, elevated; temperature service applications, high 18.1.1 Quenched and tempered martensitic stainless steel parts shall be stamped with the letters QT following the specification designation SUPPLEMENTARY REQUIREMENTS The following supplementary requirements shall apply only when specified by the purchaser in the inquiry, contract, and order with Test Method A 275/A 275M Acceptance limits shall be agreed upon between the manufacturer and purchaser S1 Macroetch Test S1.1 A sample part shall be sectioned and etched to show internal imperfections The test shall be conducted according to Test Method E 340 Details of the test shall be agreed upon between the manufacturer and the purchaser S5 Liquid Penetrant Examination S5.1 All accessible surfaces shall be examined by a liquid penetrant method in accordance with Test Method E 165 Acceptance limits shall be agreed upon between the manufacturer and the purchaser S2 Product Analysis S2.1 A product analysis in accordance with Section 11 shall be made from one randomly selected part representing each size and type (see Note 3) of part on the order If the analysis fails to comply, each part shall be checked or the lot rejected All results shall be reported to the purchaser S6 Hydrostatic Testing S6.1 A hydrostatic test at a pressure agreed upon between the manufacturer and the purchaser shall be applied by the manufacturer S3 Tension Tests S3.1 In addition to the requirements of Section 9, one tension specimen shall be obtained from a representative part from each production lot at a location agreed upon between the manufacturer and the purchaser The results of the test shall comply with Table and shall be reported to the purchaser S7 Repair Welding S7.1 No repair welding shall be permitted without prior approval of the purchaser If permitted, the restrictions of Section 14 shall apply S8 Heat Treatment Details S8.1 The manufacturer shall furnish a detailed test report containing the information required in 17.1 and shall include all pertinent details of the heat treating cycle given the parts S4 Magnetic Particle Examination S4.1 All accessible surfaces of a finished martensitic, or austenitic-ferritic stainless steel part, shall be examined by a magnetic-particle method The method shall be in accordance A 988 – 98 (2002) S14 Hardness Test S14.1 Each part shall be hardness tested and shall meet the requirements of Table S9 Material for Optimum Resistance to Stress-Corrosion Cracking S9.1 Austenitic stainless steel parts shall be furnished in the solution-annealed condition as a final operation with no subsequent cold working permitted unless specifically permitted by the purchaser S15 Heat Treatment of Austenitic Stainless Parts S15.1 The purchaser shall specify the heat treatment method in 7.1 that shall be employed S15.2 The manufacturer shall provide a test report containing the information required in 17.1 and shall include a statement of the heat treatment method employed S10 Intergranular Corrosion Tests S10.1 Intergranular corrosion tests shall be performed on specimens of austenitic stainless steel in accordance with Practices A 262 S10.2 For the austenitic stainless steels, details concerning the number of specimens and their source and location are to be a matter of agreement between the manufacturer and the purchaser S16 Grain Size for Austenitic Stainless Steels S16.1 Hot isostatically-pressed parts made from austenitic stainless steel grades other than H grades shall be tested for average grain size by Test Methods E 112 Details of the test shall be agreed upon between the manufacturer and the purchaser S11 Pitting and Crevice Corrosion Test S17 Fatigue Acceptance Test S17.1 For austenitic stainless steel components intended for service above 1000°F (540°C), a uniaxial fatigue test shall be performed S17.2 The fatigue test shall be performed in air at 1100°F (595°C) at an axial strain range of 1.0 % with a one hour hold period at the maximum positive strain point in each cycle Test specimen location and orientation shall be in accordance with the general guidance of Test Methods and Definitions A 370 and the applicable product specifications Testing shall be conducted in accord with Practice E 606 The test shall exceed 200 cycles without fracture or a 20 % drop in the load range S17.3 Failure to meet this requirement shall be cause for rejection of all parts from that blend S17.4 Test frequency shall be the same as for tension tests (see 9.5) Retesting is permitted Two additional specimens produced from the same blend shall be tested and both specimens must pass the cyclic life requirement Further retests are not permitted S11.1 The stainless steels in the final heat treated condition shall be tested in accordance with Test Method G 48 Acceptance criteria shall be a matter of agreement between the manufacturer and purchaser S12 Detrimental Intermetallic Phase Test S12.1 The austenitic-ferritic stainless steels shall be tested in accordance with the test methods given in Test Methods A 923 Acceptance criteria, if not specified in Test Methods A 923, shall be a matter of agreement between the manufacturer and the purchaser S13 Special Filler Metal S13.1 In repair welded S31600, S31603, S31609, and S31651 parts, the deposited weld metal shall conform to E 308 composition wire Parts repair welded with E 308 weld metal shall be marked S _W308 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States Individual 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